Oil burning apparatus



Sept. 27, 1932.

o. APPEL 1,879,011

OIL BURNING APPARATUS Filed Aug. 28. 1929 if I J I L r5 I 1 1 .25 52 1' m INVENTOR 0 Y scar A z vel ATTORNEY Patented Sept. 2 7, 1932 UNITED STATES OSCAR APPEL, OI PATERSQN, NEW JERSEY; ASSIGNOR TO UNI-LEC-TRIC BURNER COR- PORATION, 0F PATERSON, NEW JERSEY, A CORPORATION OF NEW JERSEY OTL BURNING APPARATUS Application filed August 28, 1929. Serial No. 388,864.

The present invention is concerned with improvements in rotary oil burners ofthe type in which fuel projected radially by a rotary distributor or projector head, is mixed and burned at a flame wall at the periphery of the hearth.

With this type of burner, highest efliciency is obtained by maintaining the combustion area, at or closely adjacent the flame wall.

The flame may be held at the wall by outwardly projecting a draft comprising thin superposed strata of air and oil, and products of combustion from the burner head through parallel trajectories which prevent sufficient mixing of the oil and air to support combustion prior to the time that the fuel particles strike the wall. In normal operation, this prevents the ring of flame from-breaking back toward the center of the hearth and igniting and burning the fuel at the head, thereby confining it to the periphery of' the hearth.

However, with burners of this type, the radial outward draft and the upflow of flame and hot gases along the flame wall induce a low pressure condition over the fuel projector which tends to pull the flames inwardly over the distributor head. Moreover, in certain types of projector heads, notably the head dis-- closed in the application of Homer A. Tiffany, Ser. No. 355,688, filed April 17, 1929,the upper surfaces of the head operateto suck back stack gases to the outlets from which the oil is'being centrifugally thrown, and mixes them with the draft mixture which is being discharged toward the flame wall, under the radially projected oil. This recirculation of stack gases, mainly nitrogen and carbon dioxide, is advantageous, in that-it maintains the head at the proper temperature, hastens the atomization of the oil fuel particles, while lengthening the time and promoting completeness of combustion of the liquid hydrocarbon. Nevertheless, the back draft of stack gases toward the head tends to cause the top of the up draft to curl or arch back toward the center and under certain conditions, it will do this before it has had time to burn out. Thus, though the flame may not break back directly .to the burner along the stream of projected oil, and air, the top of it may curl back, under certain conditions, thus causing the combustion to start in or near the burner instead of at the periphery of the hearth.

An object of the present invention is to prevent this by provision of means for directing and controlling the return circulation of the stack gas. I

This object is preferablyaccomplished by the provision of a hollow bafile, the shape and size of which is variable to suit the needs of various types of burners, but which is in most cases generally circular. It is raised above the hearth suificiently and so mounted thatit affords no substantial impedance to radial movement of the combustible draft from the projector head toward the flame wall and is of enough smaller diameter than the impact wall where combustion is initiated, so that it occupies a more or less inactive zone of the gas circulation, entirely out of the path of the upflowing part of the wall flame. It is sufficiently high and wide and the opening in its top is properly designed to permit free return of hot gases yet prevent the flame from arching back or the hot gases from flowing back through a dangerously short path which might cause it to reach the projector head before it has completely burned out.

The bafiie may be made of any suitable material which is highly heat resistant, such for instance, as metal or fire clay. It is in any event of simple, practical, inexpensive, durable construction, well suited with but slight modification for use with many types of burners.

The invention may be more fully understood from the following description in connection with the accompanying drawing, wherein Fig. 1 is a somewhat diagrammatic, vertical, sectional view through a fire box equipped with a rotary flame wall burner-and showing my improved bafiie in applied position.

.Fig. 2 is a disassembled perspective view of the three parts'of the baflie.

Fig. 3 is a vertical, sectional detail through a slightly modified form ofbafie.

The hearth 10 includes a peripheral upstanding flame wall 11 in the region of the water leg 12 of the boiler. This hearth slopes downwardly from the central opening which accommodates the projector head to the ignition trough 17 at the base of the flame Wall.

The hearth may be supported on plate 13, the edges of which rest on ledge ring 14 and the intermediate portion of which is sustained by the outwardly turned flange 15 of hollow, generally frusto-conical air collar 16 forming a liner for the central opening of the hearth.

A motor casing 18, supported on legs 19 below the hearth houses a motor (not shown) for rotating the centrifugal fuel projector head 20 here shown as constructed in accordance with the Tiffany application above identified. The means for feeding the oil to the head has not been illustrated, is not initself my invention and may be of any conventional t e.

The projector head includes a series of radial or tangential spouts 21 from which a mist of oil is thrown. Below the spouts the head is formed with a fan portion 22 sucking air from below the hearth and projecting it in a radial layer which mingles more or less with the oil spray and tends to carry itradially toward the flame wall. The upper face of said layer also tends to entrain the burned out gases which are in contact with the upper surface of said layer. The composite draft is projected above the. hearth so that thorough admixture of the fuel constituents occurs only when the draft impinges near or on the flame wall, x, which is preferably of fire clay or other catalytic material adapted to promote combustion. The impingement and mixing result preferably in a blue flame which burns upwardly in intimate heat exchange relationship with the water leg of the boiler. I

My improved baifle arrangement is here shown as a plurality of generally cylindrical bafiie rings 24, the lowermost of which is supported on slender legs 25 resting on the hearth and oflering no substantial impedance to the radial flow of fuel. The ring is of somewhat larger diameter than the projector head and its lower edge is raised high enough above the hearth to be out of the trajectory of the centrifugally thrown fuel. A similar upper bafiie ring is mounted upon the lower one and secured in an suitable manner as by feet 26 similar to eet 25, entering sockets in the upper edge of the lower ring or asshown lying inside of the lower ring.

If desirable or necessary, a flat cover plate 27 also having a baflling function may be supported upon thetop of the uppermost bafile ring and spaced thereabove, leaving a substantially unobstructed annulus 28 through which stack gases may flow back for recirculation by the projector head, heating the head and vaporozin the oil fuel therein. It will be obvious that y proper proportioning of the baffle, the return path of the draft will be controlled so that it will be burned out before it reaches the burner head; nor can burned out gases be excessively hot by the time they reach the head. The height of the baflie may even exceed the height of the'flame and the cover plate may guard against direct downflow of unduly hot gases onto the projector'head.

The cover may in many cases be omitted or the upper baflle may be of inverted cup shape with air inlet slots near its top. In fact, numerous expedients might be resorted to for attaining the desired flame bafliing and stack gas recirculation-directing action. Where the flat cover member isv used, ittoo may be supported on slender feet planted in sockets in the upper cylindrical baflle element or it may haveofi'set legs 30 as shown, including'portions 31, to rest on top of the cylindrical battle and portions 32 to lie therewithin and-center the cover. The bafile members 24 may, if desired, be

made up in a few standard diameters andheights and superposed to give the correct total height for any special size of firebox and diameter of projector head. They may, in

fact, be made in many shapesto meet the; special requirements of individual fireboxes, types of fuels, and styles of' distributor heads. I j i In Fig. 3 a baffle member 24a, corresponding to the baffle 24, is formed with a number of minute perforations 33 and acts much in the manner of the well known miners lamp,- to pass hot gases but prevent the passage of tongues of flame. Y

1. Apparatus of the class described, including a fire box, a refractory hearth closing in the bottom thereof, a rotaryhead comprising a centrifugaloil and air projector discharging horizontally above the hearth, 'and' a re- .fractory flame wall adjacent'the periphery:

of the hearth, designed and operating to in-, itiate combustion at said'wall, in combination with annular baflle means adjacent the projector permitting free supply of hot gases but preventing flame from arching backthrough the baflle from the ignition wall to the projector.

2. Apparatus of the class described, including a fire box, a refractory hearth closing in the bottom thereof, a rotary head comprising a centrifugal oil and air projector discharging horizontallyabove the hearth, and a refractory flame wall adjacent the periphery of the hearth, designed and operating to initiate combustion at said wall, in combination with annular baflle means above the projector to prevent flame but permit hotgas to arch back therethrough from the wall to the projector, said baflle being far enough above the hearth to offer no substantial impedance to the flow of fuel, and far enough-from-the ignition wall to be entirely out of the path of upflowing flame. I l

3. Apparatus of the class described, includ-' ing a fire box, a refractory hearth closing in the bottom thereof, a rotary head comprising a centrifugal oil and air projectorv discharging horizontally above the hearth, and a refractory flame wall adjacent the periphery of the hearth, designed and operating to in itiate combustion at said wall, in combination with annular baflie means above the projector and far enough above the hearth to offer no substantial impedance to the flow of fuel, and high enough to permit burning out of the flame during circulation of gases from the top of the flame downwardly through the baflie to the projector. I

4. Apparatus of the class described, including a fire box, a refractory hearth closing in the bottom thereof, a rotary head comprising a centrifugal oil and air projector discharging horizontally above the hearth, and a refractory flame wall adjacent the periphery of the hearth, designed and operating to initiate combustion at said wall, in combination with a flame baffle arranged above the projector to prevent ignition of the oil at the projector, said baffle being inthe path of hot gases and flame throwing toward the low pressure area created above the projector by rotation of the latter.

5. Apparatus of the class described, including a fire box, a refractory hearth closing in the bottom thereof, a rotary head comprising a centrifugal oil and air projector discharging horizontally above the hearth, and a refractory flame wall adjacent the periphery of the hearth, designed and operating toinitiate combustion at said wall, in combination with a flame baflie arranged above the projector to preventi ition of the oil therein, said baffle being 0 generally hollow formation and of a diameter at its base, at least approximately as great as the diameter of the projector.

6. Apparatusof the class described, including a fire box, a refractory hearth clos'ing'in the bottom thereof, a rotary head comprising a centrifugal oil and air projector discharg ing horizontally above the hearth, and a re-' fractory flame wall adjacent the periphery of the hearth, designed and operating to in itiate combustion at said wall, in combination with a flame baflie to prevent ignition of the oil therein, said 'baflie being of generally hollow formation of a diameter at its base,

at least approximately as great as the diameter of the projector and including a portion extending above the projector.

7. Apparatus of the class described, including a fire box, a refractory hearth closing in 'l the bottom thereof, a rotary head comprising a centrifugal oil and air projector dischargin'g horizontally above the hearth, and a refractory flame wall adjacent the periphery of the hearth, designed and operating to initiate combustion at said wall, in combination with a flame battle to prevent ignition of the oil therein, said baflie being of generally hollow formation of a diameter at its base, at least approximately as great as the diameter'of the projector, including a portion disposed above the projector, and having an opening therein through which hot gases may flow to heat the projector.

8. Apparatus of the class described, including a fire box, a refractory hearth closing in the bo ttom thereof, a rotary head comprising a centrifugal oil and air projector discharging horizontally above the hearth, and a refractory flame wall .adjacent the peripheryof the hearth, designed and operating to initiate combustion at said wall, in combination with a hollow flame baflie, said baflie including aportion extending above the proj ector, having an opening therein through which hot gases may flow to heat the projector and disposed out of the path of fuel pro- .jection.

9. Apparatus as setforth in claim 8 and wherein the battle is supported on the hearth by slender legs affording no substantial impedance to movement of fuel from the projector toward the flame wall.

10. Apparatus asset forth in claim 7, wherein the baflie comprises a cylindrical body supported on legs.

11. Apparatus of the class described, including a fire box, a refractory hearth closing in the bottom thereof, a rotary head comprising a centrifugal oil and air projector discharging horizontally above the hearth, and a refractory flame wall adjacent the periphery of the hearth, designed and operating to initiate combustion at said wall, in

combination with a flame baffle arranged above the projector to prevent ignition of the oil therein, the baflie comprising a plurality of stacked cylinders.

12. Apparatps of the class described, in cluding a. fire box, a refractory hearth closing in the bottom thereof, arotary head comprising a centrifugal oil and air projector discharging horizontally above the hearth, and

a fiefractory flame wall adjacent the periphery of the hearth, designed; and operating to initiate combustion at said wall, in ccmbina tion with a flame baflle arranged above the projector to prevent ignition of the oil therein, the baflie comprising a plurality of stackedcylinders, and a cover spaced thereabove affording an annular downflowpassage between itself and the uppermost cylinder.

13. Apparatus of the class described, in-

eluding a.fire box, a refractory hearth closing in the bottom thereof, a rotary head comprising a centrifugaloil and air projector discharging horizontally above the hearth, and a refractory flame wall adjacent the periphery of the hearth, designed and oper-' ating to initiate combustion at said wall, in. I

combination with a flame bafile arranged above the projector to prevent ignition of the oil therein, the bafiie comprising a hollow body having gas pervious flame excluding orifices therein. i

. 14. Apparatus as set forth in claim 8, wherein the upper end through which the hot gases enter the hollow bafile, is provided with a top cover tending to baffle direct down flow of such gas from the upper part of the fire box.

Signed at New York in the county of New York, and State of New York this 26th day of August, A. D. 1929. a

. OSCAR APPEL. 

